Part mounting device and part mounting method

ABSTRACT

A part mounting system requires a relatively small floor space for installation. A bonding apparatus ( 50 ) includes a temporary-bonding unit ( 51 ) that bonds a plurality of FPCs to which ACFs are attached, respectively, successively to a glass substrate positioned by an aligning apparatus ( 40 ), and a permanent-bonding unit ( 52 ) that bonds the plurality of FPCs temporarily bonded to the glass substrate simultaneously by heating. Each of the temporary-bonding unit ( 51 ) and the permanent-bonding unit ( 52 ) has a pair of pressing devices respectively for pressing the glass substrate and the FPC from above and from below the glass substrate. Each pressing device is capable of selectively applying either a bonding pressure or a backup pressure to the glass substrate and the electronic part.

TECHNICAL FIELD

[0001] The present invention relates to a part mounting system formounting electronic parts on a substrate and a part mounting method.More particularly, the present invention relates to a part mountingsystem that mounts electronic parts on a substrate by pressing the samethrough connecting members against the substrate, and a part mountingmethod.

BACKGROUND ART

[0002] A known part mounting system for use in fabricating a flat paneldisplay, such as a liquid crystal display, bonds electronic parts, suchas flexible printed circuits (abbreviated to “FPCs”), to a substrate,such as a glass substrate, by pressing the electronic parts throughconnecting members, such as anisotropic conductive films (abbreviated to“ACFs”), against the substrate.

[0003] There is a growing tendency for the size of panels of flat paneldisplays fabricated by using such a part mounting system to increase.Generally, a plurality of FPCs are attached by bonding to both first andsecond surfaces of a glass substrate. A conventional part mountingsystem has an upper bonding unit that presses an FPC against a glasssubstrate from above the glass substrate and a lower bonding unit thatpresses an FPC against the same glass substrate from below the glasssubstrate. The upper and the lower bonding unit are disposed atdifferent positions, respectively, beside a glass substrate carryingpath. The glass substrate is aligned with the upper bonding unit whenattaching an FPC to the first surface of the glass substrate or with thelower bonding unit when attaching an FPC to the second surface of theglass substrate, and then the FPC is pressed against and attached to theglass substrate one at a time.

[0004] This conventional part mounting system attaches FPCs to the firstand the second surface of the glass substrate by bonding by using theupper and the lower bonding unit disposed respectively at the differentpositions. Therefore, the conventional part mounting system needs alarge floor space for installation.

DISCLOSURE OF THE INVENTION

[0005] The present invention has been made in view of this problem andit is therefore an object of the present invention to provide a partmounting system that needs a relatively small floor space forinstallation, and a part mounting method.

[0006] According to a first aspect of the present invention, a partmounting system comprises: an electronic part carrying apparatus thatcarries an electronic part; a substrate feed apparatus that feeds asubstrate; an aligning apparatus that aligns an electronic part carriedby the electronic part carrying apparatus and a substrate fed by thesubstrate feed apparatus; and a bonding apparatus that bonds theelectronic part aligned with the substrate to the substrate by pressing;wherein the bonding apparatus includes a first pressing unit thatpresses the electronic part against an upper surface of the substratefrom above the substrate, and a second pressing unit that presses theelectronic part against a lower surface of the substrate from below thesubstrate, each of the first and the second pressing unit has a toolthat is applied to the substrate and the electronic part, and a pressureapplying device that selectively applies a bonding pressure or a backuppressure to the tool.

[0007] In the part mounting system in the first aspect of the presentinvention, it is preferable that the pressure applying device includes apair of lifting devices that apply the bonding pressure or the backuppressure to the tool, and a pressure adjusting device that adjusts apressure to be exerted by the lifting devices on the tool.

[0008] According to a second aspect of the present invention, a partmounting method comprises the steps of: feeding an electronic part;feeding a substrate; aligning the fed electronic part and the fedsubstrate; and bonding the electronic part aligned with the substratethrough a connecting member to the substrate; wherein the step ofbonding the electronic part to the substrate includes the steps of:selecting either a first pressing unit that presses the electronic partagainst an upper surface of the substrate from above the substrate or asecond pressing unit that presses the electronic part against a lowersurface of the substrate from below the substrate to bond the electronicpart to the substrate on the basis of electronic part mountinginformation stored in a storage device; and applying a bonding pressureto a tool included in the pressing unit selected for bonding theelectronic part to the substrate and applying a backup pressure to atool included in the other bonding unit.

[0009] The part mounting system according to the present invention isprovided with the bonding apparatus including the pair of pressing unitsthat press electronic parts against the upper and the lower surface of asubstrate, and either the bonding pressure or the backup pressure can beselectively applied to each of the pressing units. Therefore, only thepair of bonding units is necessary for attaching electronic parts bybonding to both the surfaces of the substrate and hence the partmounting system needs a relatively small floor space for installation.Since the pressure applying device has the pair of lifting devices forapplying the bonding pressure or the backup pressure to the tool, andthe pressure adjusting device for adjusting a pressure to be exerted bythe lifting devices, an optimum pressure can be used for bondingaccording to the type of electronic parts or the number of electronicparts to be simultaneously bonded to the substrate.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010]FIG. 1 is a schematic perspective view of a part mounting systemin a preferred embodiment of the present invention;

[0011]FIG. 2 is a perspective view of a modification of a glasssubstrate carrying stage included in a glass substrate feed apparatusshown in FIG. 1;

[0012]FIG. 3 is a typical view of assistance in explaining a bondingapparatus shown in FIG. 1;

[0013]FIG. 4 is a typical view of assistance in explaining amodification of the bonding apparatus shown in FIG. 3;

[0014]FIG. 5 is a block diagram of a control system for controlling thepart mounting system shown in FIG. 1;

[0015]FIG. 6 is a flow chart of assistance in explaining the operationof the part mounting system shown in FIG. 1;

[0016]FIG. 7 is a flow chart of assistance in explaining the operationof the part mounting system shown in FIG. 1;

[0017]FIG. 8 is a timing chart of assistance in explaining the generaloperation of the part mounting system shown in FIG. 1;

[0018]FIG. 9 is a timing chart of assistance in concretely explainingthe operation of a glass substrate feed apparatus shown in FIG. 1;

[0019]FIG. 10 is a timing chart of assistance in concretely explainingthe operation of a bonding apparatus shown in FIG. 1; and

[0020]FIG. 11 is a perspective view of a liquid crystal display to befabricated by using a part mounting system.

BEST MODE FOR CARRYING OUT THE INVENTION

[0021] A preferred embodiment of the present invention will be describedhereinafter with reference to the accompanying drawings. The embodimentwill be described as applied to fabricating a liquid crystal display bybonding FPCs (electronic parts) to a glass substrate (substrate) throughACFs (connecting members). As shown in FIG. 11, a liquid crystal display80 to be fabricated by using a part mounting system in a preferredembodiment of the present invention has a glass substrate 81, and aplurality of FPCs 83 bonded through ACFs 82 to the upper and lowersurface of the glass substrate 81.

[0022] Referring to FIG. 1 showing the part mounting system in thepreferred embodiment in a schematic perspective view, the part mountingsystem includes an ACF applying apparatus (connecting member applyingapparatus) 10 that applies an ACF to an FPC, an FPC carrying apparatus20 for carrying an FPC with an ACF attached thereto, a glass substratefeed apparatus 30 that feeds a glass substrate, an aligning apparatus 40for aligning the glass substrate fed thereto by the glass substrate feedapparatus 30 and the FPC carried thereto by the FPC carrying apparatus20, a bonding apparatus 50 for pressure-bonding the FPC through the ACFto the glass substrate aligned with the FPC, and a man-machine interfaceapparatus 60 for assistance for an operator to give instructions to theACF applying apparatus 10, the FPC carrying apparatus 20, the glasssubstrate feed apparatus 30, the aligning apparatus 40 and the bondingapparatus 50. The ACF applying apparatus 10, the FPC carrying apparatus20, the glass substrate feed apparatus 30, the aligning apparatus 40,the bonding apparatus 50 and the man-machine interface apparatus 60 aremounted on a base 70 to constitute a single system.

[0023] The ACF applying apparatus 10 includes an ACF applying unit 11that applies an ACF to an FPC and an FPC feed stage (electronic partfeed device)12 that feeds an FPC to the ACF applying unit 11. The ACFapplying apparatus 10 has an FPC identifying unit 13 capable ofidentifying the type and the positional state, which is represented byinclination and direction of surfaces, of an FPC fed by the FPC feedstage 12 to prevent the feed of a wrong FPC due to an erroneousoperator's operation or feed of an FPC with a wrong surface facing up.The ACF applying apparatus 10 has an ACF application state examiningunit 14 capable of quantitatively deciding the state of an ACF appliedto an FPC by the ACF applying unit 11 to prevent the reduction of yieldby avoiding quality variation due to the visual examination of the stateof the ACF on the FPC by the operator.

[0024] The FPC carrying apparatus 20 has an FPC transfer arm 21 and anFPC transfer stage 22. The FPC transfer arm 21 receives an FPC from theFPC feed stage 12 of the ACF applying apparatus 10 and transfers thesame to the FPC transfer stage 22. The FPC transfer stage 22 transfersthe FPC to an FPC carrying unit 24. The FPC carrying apparatus 20 has anFPC inverting unit (inverting mechanism) 23 capable of inverting an FPCreceived from the FPC transfer stage 22. The FPC inverting unit 23 setsan FPC with a surface thereof facing a direction required by the bondingapparatus 50 (with the right surface facing the right direction). An FPCinverted by the FPC inverting unit 23 is transferred to the FPC carryingunit 24. The FPC carrying apparatus 20 includes the FPC carrying unit 24that receives an FPC from the FPC transfer stage 22 or the FPC invertingunit 23 to the bonding apparatus 50 (aligning apparatus 40), and an FPCfeed table 25 for refeeding an FPC to the bonding apparatus 50 (aligningapparatus 40). An FPC feed operation of the FPC carrying apparatus 20for carrying an FPC from the ACF applying apparatus 10 to the bondingapparatus 50 (aligning apparatus 40) is carried out automaticallywithout the attendance of the operator to prevent the reduction of yieldby avoiding troubles, such as short circuit between terminals due to theadhesion of dust to the FPC, and to prevent feeding an FPC with a wrongsurface thereof facing a specific direction in which a right surface isto face to the bonding apparatus 50 (aligning apparatus 40).

[0025] The glass substrate feed apparatus 30 has a glass substratesupply unit 31 that supplies a glass substrate, a glass substratecarrying stage 32 capable of moving in X, Y and θ directions and ofcarrying a glass substrate received from the glass substrate supply unit31, a glass substrate transfer unit, not shown, that receives a glasssubstrate from the glass substrate carrying stage 32, and a glasssubstrate delivery unit 33 that receives a glass substrate from theglass substrate transfer unit and delivers the same to a deliveryposition. A glass substrate is transferred automatically from the glasssubstrate supply unit 31 to the glass substrate carrying stage 32 andfrom the glass substrate carrying stage 32 to the glass substratedelivery stage 33 without operator's attendance. The glass substratesupply unit 31 may be provided with a glass substrate positioning unit,not shown, for positioning a glass substrate to transfer the glasssubstrate accurately to the glass substrate carrying stage 32.

[0026]FIG. 2 shows a glass substrate carrying stage 32 in a modificationof the glass substrate carrying stage 32. As shown in FIG. 2, the glasssubstrate carrying stage 32 may be surrounded by an FPC supportmechanism 32 a, and FPCs 83 to be bonded to a glass substrate 81 placedon the glass substrate carrying stage 32 may be supported on the FPCsupport mechanism 32 a. Thus, it is possible to prevent the FPCs 83 fromdrooping and interfering with other units and falling off the glasssubstrate 81, which effectively prevents delay in supplying anddelivering the glass substrate 81.

[0027] The aligning apparatus 40 has an image pickup device 41 thatforms an image of a glass substrate placed on the glass substratecarrying stage 32 of the glass substrate feed apparatus 30 and an FPCcarried by the FPC carrying unit 24 of the FPC carrying apparatus 20.The aligning apparatus 40 has an image processing device, not shown,that recognizes the position of the glass substrate and the positionalrelation between the glass substrate and the FPC from an image formed bythe image pickup device 41. The aligning apparatus 40 corrects therespective positions of the glass substrate carrying stage 32 and theFPC carrying unit 24 on the basis of the result of recognition made bythe image processing device. The position of the glass substratecarrying stage 32 is corrected on the basis of the position of the glasssubstrate recognized by the image processing device and the position ofthe FPC carrying unit 24 is corrected on the basis of the positionalrelation between the glass substrate and the FPC recognized by the imageprocessing device to align the glass substrate and the FPC. Thisaligning method is capable of achieving the alignment of the glasssubstrate and the FPC in a high accuracy as compared with that in whichthe glass substrate and the FPC can be aligned by a conventionalaligning method using mechanical means, such as gauging. The positionalrelation between the glass substrate and the FPC may be corrected bycorrecting the position of the glass substrate carrying stage 32.

[0028] The bonding apparatus 50 has a temporary bonding unit(temporary-bonding device) 51 that bonds successively a plurality ofFPCs provided with ACFs for temporary bonding to a glass substratecorrectly positioned by the aligning apparatus 40, and apermanent-bonding unit (permanent-bonding device) 52 that heats andpresses simultaneously the plurality of FPCs temporarily bonded to theglass substrate for permanent bonding.

[0029]FIG. 3 is a typical view of the temporary-bonding unit 51 shown inFIG. 1. As shown in FIG. 3, the temporary-bonding unit 51 has a firstpressing device 53 that applies a pressure from above a glass substrateand an FPC, and a second pressing device 54 that applies a pressure frombelow a glass substrate and an FPC. The first pressing device 53 has anupper tool 55 that is brought into contact with the upper surfaces ofthe glass substrate and the FPC, and a pair of cylinder actuators(lifting devices) 53 a and 53 b. The cylinder actuator 53 a applies atemporary-bonding pressure to the lower tool 55, and the other cylinderactuator 53 b applies a backup pressure to the lower tool 55. The secondpressing device 54 has a lower tool 56 that is brought into contact withthe lower surfaces of the glass substrate and the FPC, and a pair ofcylinder actuators (lifting devices) 54 a and 54 b. The cylinderactuator 54 a applies a temporary-bonding pressure to the lower tool 56,and the other cylinder actuator 54 b applies a backup pressure to thelower tool 56. The upper tool 55 and the lower tool 56 are disposedopposite to each other. The cylinder actuators 53 a and 53 b are fixedto an upper setting surface 57, and the cylinder actuators 54 a and 54 bare fixed to a lower setting surface 58. The cylinder actuators 53 a and53 b (54 a and 54 b) and pressure adjusting devices 73, which will bedescribed later, constitute a pressure applying device.

[0030] When temporarily bonding an FPC to the upper surface of a glasssubstrate by the temporary bonding unit 51, the lower cylinder actuator54 b, which applies the backup pressure to the lower tool 56, raises thelower tool 56 to a backup position, and the upper cylinder actuator 53a, which applies the temporary-bonding pressure to the upper tool 55,lowers the upper tool 55 to a pressing position. When temporarilybonding an FPC to the lower surface of a glass substrate by thetemporary-bonding unit 51, the upper cylinder actuator 53 b, whichapplies the backup pressure to the upper tool 55, lowers the upper tool55 to a backup position, and the lower cylinder actuator 54 a, whichapplies the temporary-bonding pressure to the lower tool 56, raises thelower tool 56 to a pressing position. The backup pressure to be appliedto the upper tool 55 and the lower tool 56 by the cylinder actuators 53b and 54 b is higher than the temporary-bonding pressure to be appliedto the upper tool 55 and the lower tool 56 by the cylinder actuators 53a and 54 a. The cylinder actuators 53 b and 54 b for backup may beprovided with locking mechanisms to produce a pressure (reaction force)corresponding to the pressure exerted by the cylinder actuators 53 a and54 a for temporary bonding.

[0031] The permanent-bonding unit 52 shown in FIG. 1 may be the same inconstruction as the temporary-bonding unit 51 shown in FIG. 3. In thetemporary-bonding unit 51 shown in FIG. 3, the cylinder actuators 53 aand 53 b are disposed in a parallel arrangement with respect to theupper tool 55, and the cylinder actuators 54 a and 54 b are disposed ina parallel arrangement with respect to the lower tool 56. The cylinderactuators 53 a and 53 b may be disposed in a series arrangement withrespect to the upper tool 55, and the cylinder actuators 54 a and 54 bmay be disposed in a series arrangement with respect to the lower tool56 as shown in FIG. 4. The bonding apparatus 50 may be further providedwith pressure adjusting devices 73 (FIG. 5), such as electropneumaticregulators, to adjust the temporary-bonding pressure and thepermanent-bonding pressure according to the type of FPCs and the numberof FPCs that are pressed simultaneously for permanent bonding. Theelectropneumatic regulators or the like may be properly controlled bythe operator or may be controlled by a controller on the basis ofinformation about the types of glass substrates and FPCs. In FIGS. 3 and4, more than two cylinder actuators may be used for operating each ofthe tools 55 and 56. Each of the tools 55 and 56 may be operated by asingle cylinder actuator capable of exerting variable pressure to thetool 55 or 56.

[0032] The man-machine interface apparatus 60 has touch-sensitive panels61 and 62 for controlling the operations of the ACF applying apparatus10 and the FPC carrying apparatus 20, and a control panel 63 forcontrolling the operation of the glass substrate feed apparatus 30. Thecontrol panel 63 is provided with push-button switches for variousfunctions.

[0033] As shown in FIG. 5, a controller 71 controls the ACF applyingapparatus 10, the FPC carrying apparatus 20, the glass substrate feedapparatus 30, the aligning apparatus 40, the first pressing device 53and the second pressing device 54 (cylinder actuators 53 a, 53 b, 54 aand 54 b) of the bonding apparatus 50 and the man-machine interfaceapparatus 60 (touch-sensitive panels 61 and 62 and the control panel63). A storage device 72 is connected to the controller 71. Electronicpart mounting information is stored in the storage device 72. Theelectronic part mounting information includes data on the positions ofFPCs on a glass substrate, a surface to which FPCs are to be bonded,i.e., the upper or the lower surface of the glass substrate to whichFPCs are to be bonded, and the types of FPCs bonded at specifiedpositions on a glass substrate and such.

[0034] The operation of this embodiment will be described with referenceto FIGS. 6 to 10. FIGS. 6 and 7 are flow charts of assistance inexplaining the operation of the part mounting system shown in FIG. 1,and FIGS. 8 to 10 are timing charts of assistance in concretelyexplaining the operations shown in FIGS. 6 and 7.

Operations for Bonding ACFs to FPCs and Carrying FPCs

[0035] The operator enters an operation start instruction by operatingthe touch-sensitive panel 61. Then, the ACF applying unit 11 starts apreparatory operation for ACF application and the FPC feed stage 12moves to an FPC supply position.

[0036] Then, the operator takes out an FPC identified by an FPC numberdisplayed on the touch-sensitive panel 61 from an FPC tray, not shown(step 101) and puts the FPC taken out of the FPC tray on the FPC feedstage 12 (step 102). After fixing the FPC on the FPC feed stage 12 bysuction, the operator enters an FPC feed instruction by operating thetouch-sensitive panel 61.

[0037] Subsequently, the FPC feed stage 12 carries the FPC to the FPCidentifying unit 13. The FPC identifying unit 13 inspects the FPC to seewhether or not the FPC is the one indicated by the FPC number displayedon the touch-sensitive panel 61.

[0038] The FPC identifying unit 13 examines the type and condition ofthe FPC fed by the FPC feed stage 12 (step 103). If the FPC is a rightone, the FPC feed stage 12 carries the FPC to the ACF applying unit 11(step 104). If the FPC is a wrong one, the FPC feed stage 12 carries theFPC back to the FPC supply position (step 104).

[0039] An instruction requesting the replacement of the wrong FPC with aright one is displayed on the touch-sensitive panel 61. The operatorreplaces the wrong FPC with a right one, and enters an operation startinstruction again by operating the touch-sensitive panel 61. The FPCidentifying step is executed again.

[0040] Subsequently, the ACF applying unit 11 applies an ACF to the FPCfed by the FPC feed stage 12 (step 105).

[0041] After the ACF has been applied to the FPC by the ACF applyingunit 11, the FPC feed stage 12 carries the FPC to the ACF applicationstate examining unit 14.

[0042] The ACF application state examining unit 14 examines the state ofthe ACF applied to the FPC by the ACF applying unit 11 (step 106). Ifthe state of the ACF on the FPC is right, the FPC feed stage 12 carriesthe FPC to an FPC transfer position (step 107). If the state of the ACFon the FPC is wrong, the FPC feed stage 12 returns the FPC to the FPCsupply position (step 107).

[0043] In the latter case, the operator replaces the FPC to which theACF has been wrongly applied with a new FPC and enters an FPC feedinstruction again by operating the touch-sensitive panel 61. The FPCidentifying step, the ACF applying step and the ACF application stateexamining step are executed again.

[0044] The FPC to which the ACF is applied correctly is transferred fromthe FPC feed stage 12 to the FPC transfer stage 22 by the FPC transferarm 21 (step 108).

[0045] The FPC transfer stage 22 receives the FPC from the FPC transferarm 21, moves to an FPC transfer position where the FPC is transferredto the FPC carrying unit 24. If one of the sides of the FPC to be facingdown on the bonding apparatus 50 is facing up on the FPC transfer stage22, the FPC is transferred from the FPC transfer stage 22 to the FPCinverting unit 23, and the FPC is transferred from the FPC invertingunit 23 to the FPC carrying unit 24 after being inverted.

[0046] More concretely, the controller 71 decides the position of theFPC relative to a glass substrate on the basis of electronic partmounting information stored in the storage device 72. If the FPC is tobe bonded to the upper side of the glass substrate, the FPC invertingunit 23 inverts the FPC. If the FPC is to be bonded to the lower side ofthe glass substrate, the FPC inverting unit 23 does not operate. The FPCis inverted when the sane is to be bonded to the upper surface of theglass substrate to make the ACF applied to the upper side of the FPC bythe ACF applying unit 11 face down.

[0047] The FPC thus transferred to the FPC carrying unit 24 is carriedto the bonding apparatus 50 (aligning apparatus 40).

[0048] Steps 101 to 108 are repeated a number of times equal to thenumber of FPCs to be permanently bonded simultaneously to a glasssubstrate by the permanent-bonding unit or equal to the number of FPCsto be bonded to one glass substrate (step 109). Steps 101 to 109 arerepeated until the operation of the part mounting system is completed(step 110).

[0049] When four FPCs are bonded to a glass substrate in two sets of twoFPCs, the FPCs are fed, ACF are applied to the FPCs and the FPCs arecarried by operations shown in FIG. 8. As shown in FIG. 8, operationsfor applying ACFs to FPCs and those for bonding the FPCs to the glasssubstrate (temporary bonding and permanent bonding) are carried outseparately. While a glass substrate is in a bonding process for bondingFPCs to the glass substrate, FPCs to be bonded to another glasssubstrate can be prepared, so that the throughput of the part mountingsystem can be increased. In FIG. 8, a temporary bonding process and apermanent bonding process are shown in a single process for simplicity.

Glass Substrate Feeding

[0050] The operator takes out a glass substrate from a glass substratecarrier, not shown, and feeds the same to the glass substrate supplyunit 31 (step 201). The operator positions the glass substrate on theglass substrate supply unit 31 by a glass substrate positioning device,not shown, and depresses a push button on the control panel 63 to notifythe controller 71 of the completion of feeding the glass substrate.

[0051] The glass substrate fed to the glass substrate supply unit 31 istransferred from the glass substrate supply unit 31 to the glasssubstrate carrying stage 32 by lifting pins, not shown, included in theglass substrate carrying stage 32.

[0052] The glass substrate carrying stage 32 carries the glass substratereceived from the glass substrate supply unit 31 to the bondingapparatus 50 (aligning apparatus 40). The glass substrate carrying stage32 transfers the glass substrate provided with FPCs bonded thereto bythe bonding apparatus 50 through a glass substrate transfer unit, notshown, to the glass substrate delivery unit 33. The operator takes outthe glass substrate from the glass substrate delivery unit 33.

[0053] When bonding four FPCs in two sets of two FPCs to a glasssubstrate, the glass substrate is supplied, carried and returned asshown in FIGS. 8 and 9(a). Referring to FIGS. 8 and 9(a), operations forsupplying and taking out a glass substrate are carried out separatelyfrom those for carrying a glass substrate. Therefore, while FPCs arebeing bonded to a glass substrate, another glass substrate can besupplied. Thus, a throughput that can be achieved by the part mountingsystem by carrying out a procedure shown in FIG. 9(a) is greater thanthat can be achieved by the part mounting system by carrying out aconventional procedure shown in FIG. 9(b).

Positioning of Glass Substrate and FPC

[0054] Upon the reception of a glass substrate, the glass substratecarrying stage 32 carries the glass substrate to an alignment markrecognizing position on the aligning apparatus 40 to position the glasssubstrate by an image processing operation. The aligning apparatus 40forms an alignment mark image of an alignment mark formed on the glasssubstrate carried thereto by the glass substrate carrying stage 32 bythe image pickup device 41, and an image processing device, not shown,recognizes the position of the glass substrate from the alignment markimage formed by the image pickup device 41 (step 202).

[0055] When an FPC is transferred from the ACF applying apparatus 10 tothe FPC carrying apparatus 20 (step 203), the FPC carrying unit 24 ofthe FPC carrying apparatus 20 carries the FPC to a lead recognizingposition on the aligning apparatus 40 to position the FPC relative tothe glass substrate by image processing (step 204).

[0056] Then, the controller 71 corrects the position of the glasssubstrate carrying stage 32 with reference to the position of the glasssubstrate recognized by the image processing device in step 202 andcarries the glass substrate to the lead recognizing position on thealigning apparatus 40 (step 205).

[0057] An image of the leads of the glass substrate and the FPC carriedto the lead recognizing position on the aligning apparatus 40 is formedby the image pickup device 41, and the positional relation between theleads of the glass substrate and those of the FPC is recognized by animage processing device, not shown (step 206). Then, the controller 71corrects the position of the FPC carrying unit 24 with reference to thepositional relation between the glass substrate and the FPC recognizedby the image processing device to align the FPC with the glass substrate(step 207).

[0058] When the FPC cannot be correctly recognized by the imageprocessing operation for processing the image of the glass substrate andthe FPC placed in the aligning apparatus 40, and the image processingdevice or the operator decides that the FPC is defective, it ispreferable to carry away the FPC by the FPC feed table 25 and to supplya right FPC of the same type. The operator supplies the right FPC to theFPC feed table 25 after taking out the rejected FPC from the FPC feedtable 25. The FPC thus supplied must be provided with an ACF.

Bonding FPC to Glass Substrate

[0059] After the FPC has been thus aligned with the glass substrate, theFPC is bonded temporarily through the ACF to the glass substrate by thetemporary-bonding unit 51 (step 208) Steps 203 to 208 are repeated anumber of times equal to the number of FPCs to be permanently bondedsimultaneously to a glass substrate by the permanent-bonding unit 52(step 209). After the predetermined number of FPCs have been temporarilybonded to the glass substrate, the glass substrate carrying stage 32carries the glass substrate to the permanent-bonding unit 52. Thepermanent-bonding unit 52 bonds the FPCs temporarily bonded to the glasssubstrate simultaneously to the glass substrate for permanent bonding(step 210).

[0060] Steps 201 to 210 are repeated until all the FPCs temporarilybonded to the glass substrate are bonded permanently to the glasssubstrate (step 211). Steps 201 to 211 are repeated until the operationof the part mounting system is completed (step 212).

[0061] The controller 71 of the part mounting system selects either thefirst pressing device 53 or the second pressing device 54 on the basisof electronic part mounting information stored in the storage device 72for temporary bonding and permanent bonding, and controls the operationsof the cylinder actuators 53 a and 53 b and the cylinder actuators 54 aand 54 b according to the result of selection. When the FPCs are to bebonded to the upper surface of the glass substrate, the lower tool 56 isused for supporting the glass substrate and the upper tool 55 is usedfor bonding. When the FPCs are to be bonded to the lower surface of theglass substrate, the upper tool 55 is used for supporting the glasssubstrate and the lower tool 56 is used for bonding.

[0062] When bonding six FPCs in two sets of two FPCs to one glasssubstrate, the FPCs are bonded temporarily and permanently to the glasssubstrate by a bonding procedure shown in FIG. 10(a). Referring to FIG.10(a), the temporary-bonding unit 51 temporarily bonds two FPCssuccessively to the glass substrate, and then the permanent-bonding unit52 carries out a permanent-bonding process to bond the two FPCstemporarily bonded to the glass substrate simultaneously to the glasssubstrate for permanent bonding. Thus, the number of cycles of thepermanent-bonding process, which takes more time than atemporary-bonding process, can be reduced. Thus, a throughput that canbe achieved by the part mounting system by carrying out the bondingprocedure shown in FIG. 10(a) is greater than that can be achieved bythe part mounting system by carrying out a conventional bondingprocedure shown in FIG. 10(b).

[0063] In this embodiment, the temporary-bonding unit 51 bonds aplurality of FPCs successively to a glass substrate, and then thepermanent-bonding unit 52 bonds the FPCs temporarily bonded to the glasssubstrate simultaneously for permanent bonding. Consequently, the numberof cycles of the permanent-bonding process for each glass substrate canbe reduced, which increases the throughput of the part mounting system.

[0064] In this embodiment, the temporary-bonding unit 51 or thepermanent-bonding unit 52 is provided with the pair of pressing devicesto press a glass substrate and a FPC from above and from below the same,and the pair of pressing devices are used selectively for applyingeither the bonding pressure or the backup pressure. Thus, FPCs can bebonded to both the surfaces of a glass substrate by using the pair ofpressing devices, which reduces floor space necessary for installing thepart mounting system.

[0065] In this embodiment, pressures to be applied to the cylinderactuators 53 a and 53 b and the cylinder actuators 54 a and 54 b of eachof the temporary-bonding unit 51 and the permanent-bonding unit 52 areadjusted to proper pressures for temporary bonding and permanent bondingby the pressure adjusting devices 73 according to the type of FPC andthe number of FPCs to be simultaneously bonded to the glass substratefor permanent bonding.

[0066] In this embodiment, the controller 71 inverts the FPCsselectively according to the electronic part mounting information storedin the storage device 72 to feed the FPCs to the bonding apparatus 50 inpositions corresponding to the positions of the FPCs on the glasssubstrate. Thus, desired FPCs can be surely bonded to desired portionsof the glass substrate.

[0067] In this embodiment, the controller 71 uses either the firstpressing device 53 or the second pressing device 54 selectively forbonding according to the electronic part mounting information stored inthe storage device 72. Thus, the first pressing device 53 and the secondpressing device 54 are able to apply pressures suitable for the surfacesof the glass substrate to which the FPCs are bonded, so that the FPCscan be satisfactorily bonded to the glass substrate.

[0068] In the foregoing embodiment, the FPC is bonded to the glasssubstrate after applying the ACF to the FPC by the ACF applyingapparatus 10. The FPC may be bonded to the glass substrate afterapplying the ACF to the glass substrate.

[0069] In the foregoing embodiment, the glass substrate carrying stage32 is provided with the FPC support mechanism for supporting FPCs bondedto the glass substrate. The temporary-bonding unit 51 and thepermanent-bonding unit 52 may be provided with such an FPC supportmechanism as that included in the glass substrate carrying stage 32.

[0070] Although the present invention has been described as applied tothe manufacture of a liquid crystal display, the present invention isnot limited thereto in its practical application and is applicable tothe manufacture of panel-shaped display devices, such as plasma displaypanels. In the foregoing description of the preferred embodiment,electronic parts are FPCs and connecting members are ACFs, naturally,electronic parts and connecting members may be those other than FPCs andACFs.

[0071] The present invention is applied to both the temporary-bondingunit 51 and the permanent-bonding unit 52 in the foregoing embodiment,the present invention may be applied only to either thetemporary-bonding unit 51 or the permanent-bonding unit 52.

1. A part mounting system comprising: an electronic part carryingapparatus that carries an electronic part; a substrate feed apparatusthat feeds a substrate; an aligning apparatus that aligns an electronicpart carried by the electronic part carrying apparatus and a substratefed by the substrate feed apparatus; and a bonding apparatus that bondsthe electronic part aligned with the substrate to the substrate bypressing; wherein the bonding apparatus includes a first pressing unitthat presses the electronic part against an upper surface of thesubstrate from above the substrate, and a second pressing unit thatpresses the electronic part against a lower surface of the substratefrom below the substrate, each of the first and the second pressing unithas a tool that is applied to the substrate and the electronic part, anda pressure applying device that selectively applies a bonding pressureor a backup pressure to the tool.
 2. The part mounting system accordingto claim 1, wherein the pressure applying device includes a pair oflifting devices that apply the bonding pressure or the backup pressureto the tool, and a pressure adjusting device that adjusts a pressure tobe exerted by the lifting devices on the tool.
 3. The part mountingsystem according to claim 1, further comprising: a storage device thatstores electronic part mounting information; and a controller thatselects either the first pressing device or the second pressing devicefor bonding on the basis of the electronic part mounting informationstored in the storage device, and controls the pressure applying deviceto apply a bonding pressure to the tool of one of the first and thesecond pressing device, selected as a bonding means and applies a backuppressure to the other pressing device.
 4. The part mounting systemaccording to claim 1, further comprising: an inverting mechanism thatinverts an electronic part to be carried by the electronic part carryingapparatus; a storage device that stores electronic part mountinginformation; and a controller that controls the inverting mechanism soas to invert an electronic part selectively on the basis of theelectronic part mounting information.
 5. The part mounting systemaccording to claim 1, further comprising: a storage device that storeselectronic part mounting information; an inverting mechanism thatinverts an electronic part to be carried by the electronic part carryingapparatus; and a controller that selects either the first pressingdevice or the second pressing device for bonding on the basis of theelectronic part mounting information stored in the storage device, andcontrols the pressure applying device to apply a bonding pressure to thetool of one of the first and the second pressing device, selected as abonding means and applies a backup pressure to the other pressingdevice; wherein the controller further controls the inverting mechanismso as to invert an electronic part selectively on the basis of theelectronic part mounting information.
 6. The part mounting systemaccording to claim 1, wherein the substrate feed apparatus is providedwith a support mechanism that supports electronic parts bonded to asubstrate by the bonding apparatus.
 7. A part mounting systemcomprising: an electronic part carrying apparatus that carries anelectronic part; a connecting member applying apparatus that applies aconnecting member to the electronic part carried by the electronic partcarrying apparatus; an electronic part carrying apparatus that carriesthe electronic part to which a connecting member has been applied by theconnecting member applying apparatus; a substrate feed apparatus thatfeeds a substrate; an aligning apparatus that aligns an electronic partcarried by the electronic part carrying apparatus and a substrate fed bythe substrate feed apparatus; a temporary-bonding apparatus thattemporarily bonds together the electronic part and the substrate alignedwith each other by the aligning apparatus through a connecting memberapplied to the electronic part; and a permanent-bonding apparatus thatpermanently bonds an electronic part temporarily bonded to a substrateby the temporary-bonding apparatus to the substrate; wherein thetemporary-bonding apparatus includes a first pressing unit that pressesan electronic part against an upper surface of a substrate from abovethe substrate, and a second pressing unit that presses an electronicpart against a lower surface of a substrate from below the substrate,and each of the first and the second bonding unit has a tool that isapplied to the substrate and the electronic part, and a pressureapplying device that selectively applyies a bonding pressure or a backuppressure to the tool.
 8. The part mounting system according to claim 7,wherein the pressure applying device includes a pair of lifting devicesthat apply the bonding pressure or the backup pressure to the tool, anda pressure adjusting device that adjusts a pressure to be exerted by thelifting devices on the tool.
 9. The part mounting system according toclaim 7, further comprising: a storage device that stores electronicpart mounting information; and a controller that selects either thefirst pressing device or the second pressing device for bonding on thebasis of the electronic part mounting information stored in the storagedevice, and controls the pressure applying device to apply a bondingpressure to the tool of one of the first and the second pressing device,selected as a bonding means and applies a backup pressure to the otherpressing device.
 10. The part mounting system according to claim 7,further comprising: an inverting mechanism that inverts an electronicpart to be carried by the electronic part carrying apparatus; a storagedevice that stores electronic part mounting information; and acontroller that controls the inverting mechanism so as to invert anelectronic part selectively on the basis of the electronic part mountinginformation.
 11. The part mounting system according to claim 7, furthercomprising: a storage device that stores electronic part mountinginformation; an inverting mechanism that inverts an electronic part tobe carried by the electronic part carrying apparatus; and a controllerthat selects either the first pressing device or the second pressingdevice for bonding on the basis of the electronic part mountinginformation stored in the storage device, and controls the pressureapplying device to apply a bonding pressure to the tool of one of thefirst and the second pressing device, selected as a bonding means andapplies a backup pressure to the other pressing device; wherein thecontroller further controls the inverting mechanism so as to invert anelectronic part selectively on the basis of the electronic part mountinginformation.
 12. The part mounting system according to claim 7, whereinthe substrate feed apparatus is provided with a support mechanism thatsupports electronic parts bonded to a substrate by the bondingapparatus.
 13. A part mounting method comprising the steps of: feedingan electronic part; feeding a substrate; aligning the fed electronicpart and the fed substrate; and bonding the electronic part aligned withthe substrate through a connecting member to the substrate; wherein thestep of bonding the electronic part to the substrate includes the stepsof: selecting either a first pressing unit that presses the electronicpart against an upper surface of the substrate from above the substrateor a second pressing unit that presses the electronic part against alower surface of the substrate from below the substrate to bond theelectronic part to the substrate on the basis of electronic partmounting information stored in a storage device; and applying a bondingpressure to a tool included in the pressing unit selected for bondingthe electronic part to the substrate and applying a backup pressure to atool included in the other bonding unit.